We aimed to assess whether the immunological abnormalities which have been observed in patients with loose total hip replacements (THRs) are present in patients with a well-fixed prosthesis. We examined blood samples from 39 healthy donors, 22 patients before THR and 41 with well-fixed THRs of different types (15 metal-on-metal, 13 metal-on-polyethylene, 13 ceramic-on-ceramic). Before THR, the patients showed a decrease in leukocytes and myeloid cells in comparison with healthy donors, and a prevalence of type-1 T lymphocytes, which was confirmed by the increase in ratio of interferon-γ to interleukin 4. Moreover, patients with metal-on-metal or metal-on-polyethylene implants showed a significant decrease in the number of T lymphocytes and a significant increase in the serum level of chromium and cobalt, although no significant correlation was observed with the immunological changes. In the ceramic-on-ceramic group, leukocytes and lymphocyte subsets were not significantly changed, but a significant increase in type-2 cytokines restored the ratio of interferon-γ to interleukin 4 to normal values. We conclude that abnormalities of the cell-mediated immune response may be present in patients with a well-fixed THR, and that the immunological changes are more evident in those who have at least one metal component in the articular coupling.
Objectives. Acetabular component orientation in total hip arthroplasty (THA)
influences results. Intra-operatively, the natural arthritic acetabulum
is often used as a reference to position the acetabular component.
Detailed information regarding its orientation is therefore essential. The
aim of this study was to identify the acetabular inclination and
anteversion in arthritic hips. Methods. Acetabular inclination and anteversion in 65 symptomatic arthritic
hips requiring THA were measured using a computer navigation system.
All patients were Caucasian with
This study reports on a secondary exploratory analysis of the early clinical outcomes of a randomised clinical trial comparing robotic arm-assisted unicompartmental knee arthroplasty (UKA) for medial compartment osteoarthritis of the knee with manual UKA performed using traditional surgical jigs. This follows reporting of the primary outcomes of implant accuracy and gait analysis that showed significant advantages in the robotic arm-assisted group. A total of 139 patients were recruited from a single centre. Patients were randomised to receive either a manual UKA implanted with the aid of traditional surgical jigs, or a UKA implanted with the aid of a tactile guided robotic arm-assisted system. Outcome measures included the American Knee Society Score (AKSS), Oxford Knee Score (OKS), Forgotten Joint Score, Hospital Anxiety Depression Scale, University of California at Los Angeles (UCLA) activity scale, Short Form-12, Pain Catastrophising Scale, somatic disease (Primary Care Evaluation of Mental Disorders Score), Pain visual analogue scale, analgesic use, patient satisfaction, complications relating to surgery, 90-day pain diaries and the requirement for revision surgery.Objectives
Methods
Osteoporosis and abnormal bone metabolism may prove to be significant
factors influencing the outcome of arthroplasty surgery, predisposing
to complications of aseptic loosening and peri-prosthetic fracture.
We aimed to investigate baseline bone mineral density (BMD) and
bone turnover in patients about to undergo arthroplasty of the hip
and knee. We prospectively measured bone mineral density of the hip and
lumbar spine using dual-energy X-ray absorptiometry (DEXA) scans
in a cohort of 194 patients awaiting hip or knee arthroplasty. We
also assessed bone turnover using urinary deoxypyridinoline (DPD),
a type I collagen crosslink, normalised to creatinine.Aims
Methods
Recently, femoroacetabular impingement has been recognised as a cause of early osteoarthritis. There are two mechanisms of impingement: 1) cam impingement caused by a non-spherical head and 2) pincer impingement caused by excessive acetabular cover. We hypothesised that both mechanisms result in different patterns of articular damage. Of 302 analysed hips only 26 had an isolated cam and 16 an isolated pincer impingement. Cam impingement caused damage to the anterosuperior acetabular cartilage with separation between the labrum and cartilage. During flexion, the cartilage was sheared off the bone by the non-spherical femoral head while the labrum remained untouched. In pincer impingement, the cartilage damage was located circumferentially and included only a narrow strip. During movement the labrum is crushed between the acetabular rim and the femoral neck causing degeneration and ossification. Both cam and pincer impingement lead to osteoarthritis of the hip. Labral damage indicates ongoing impingement and rarely occurs alone.
